Summary: This paper appears in Proceedings of the 1996 ACM SIGMOD Int. Conf. on Management of Data, Montreal, Canada, June 1996.
Note: the pages are numbered 318329, as in the proceedings.
Safe and Efficient Sharing of Persistent Objects in Thor
B.Liskov, A.Adya, M.Castro, M.Dayy, S.Ghemawatz, R.Gruberx, U.Maheshwari, A.C.Myers, L.Shrira
Laboratory for Computer Science,
Massachusetts Institute of Technology,
545 Technology Square, Cambridge, MA 02139
Thor is an object-oriented database system designed for use in a
heterogeneous distributed environment. It provides highly-reliable
and highly-available persistent storage for objects, and supports
safe sharing of these objects by applications written in different
Safe heterogeneous sharing of long-lived objects requires
encapsulation: the system must guarantee that applications interact
with objects only by invoking methods. Although safety concerns
are important, most object-oriented databases forgo safety to avoid
paying the associated performance costs.
This paper gives an overview of Thor's design and implementa-